Check this out: Fiber Optic ESC Cable

[Brett_Warwick]

Hi All,

I was having interference problems with my setup on 35mhz. So i built this Fiber optic Esc Cable.

The perfect solution:

1. Best isolation you can get
2. Lightweight compared to toroids
3. Stick your receiver anywhere you like, works up to 100mtrs
4. Guaranteed to work every time
5. Low cost

[darkith]

Neat!

Would using an opto-isolator work as well?

D.

[Acetronics]

Hi Brett,

Motorola devices ( MFOD/MFOE ) are much too slow here to have a good signal transmission ...
Devices intended for audio transmission work pretty well here ...

Very good solution. I use it aboard my model boats ( 2 x speed 700 12v motors )

Alain

[Andy W]

Neat!

Would using an opto-isolator work as well?

D.

Yes.. that's what most OPTO ESC's have.. :)
..a

[jperch]

That is a pretty neat idea! Any ideas on cost?

Joe

[Brett_Warwick]

RF noise can still leek past an Opto isolators.

This unit cost me about $10.00 Aus to make the TX RX units are IF-E96 at $3.00 each.
I have now encased them in heatshink they look pretty neat.

[sesat]

Brett, do these optical transeivers act as a black box? Can I put in any PWM or TTL signal into one end, and have it come out the other?


Ram.

[Brett_Warwick]

Yep any TTL signal under 2 Mhz its basically contains a led at one end and a phototransistor at the other in a neat little housing that holds a fiber optic cable.
I use the bec on the speedy to power the circuit on the other side.

[lazy-b]

Hey, thats a Neat Idea...maybe I just need a Fiber Optic cable only, just glue-gun it to the end of Super Bright LED and Photo Transistor, then Heat Shrink it.

Guys: my friend working on a fiber optics cabling, they say its very dangerous working on Fiber optics, specially during cutting, cause a bits of fiber optics is so thin, it can penetrate on human skin...they make sure all bits of fiber optics is put on a masking tape.

[badcockr]

<snip>
Guys: my friend working on a fiber optics cabling, they say its very dangerous working on Fiber optics, specially during cutting, cause a bits of fiber optics is so thin, it can penetrate on human skin...they make sure all bits of fiber optics is put on a masking tape.

Not true for the cable used here.

Communications optical fibre is 125 um silica fibre (monomode) which can only be cleaved using specialist tools that a modeller will not have.

This fibre is 1 mm PMMA plastic optical fibre (POF) typically used in automotive systems or in optical links for audio systems. Handling is very easy and the fibre is cheap and easily available. No specialist tools are required apart from a sharp blade to cut (cleave) the fibre. Because of the large diameter this poses no safety problems.

HTH

Rod

[lazy-b]

Rod, thats Nice to know.

one useful use of fiber optics cable is that you can use it for monitoring the Tail Light of your Motorcycle or Car......just install a optics cable from the Tail light to the front Dash Board.....this will really give you a true feedback, so that you really know if your tail light is really working.

Regards

Ellion

[CrashingDutchman]

Brett,

RF noise can still leek past an Opto isolators.

This unit cost me about $10.00 Aus to make the TX RX units are IF-E96 at $3.00 each.
I have now encased them in heatshink they look pretty neat.

I have a couple of questions:
- Can you give us any information what is needed to make this?
- Where can we buy stuff like this (preferably a company that accepts PayPal and ships internationally).
- Is it only used between the receiver and the brushless controller?
- Any information on weight?

Thanks!

CD

[AndyKunz]

You can get them here as well.

http://www.aerografixs.com/

I have a set and it works great. Roger is very easy to talk to as well. You may have met him if you go to the Toledo show.

Andy

[CrashingDutchman]

Would love to go, but since I am from The Netherlands, it's a bit far...

CD

[sesat]

I am looking online for the parts. Could someone help me with basic electronics terminology? It seems I could choose from a "photodiode", "phototransistor", "photodarlington", and "photologic detectors" with either "totem pole" or "open collector" outputs.

I'm just trying to make a substitute for a two-wire I2C bus. Which receiver part should i use, ideally I want an output of only either 0V or 5V with no swing in between, with a high signal on the LED side corresponding with a "on" state in the optical fibre and a high signal coming out of the receiver part.

Thanks, I would appreciate any help I can get.


Ram.

[Warske]

...maybe I just need a Fiber Optic cable only, just glue-gun it to the end of Super Bright LED and Photo Transistor, then Heat Shrink it. Good idea. :) I tried that a while ago using an IR LED and photo transisistor. It worked great. No need for Super Bright. I only tried it with multi filament fiber, not the mono filament, but both should work. Test results: http://www.rcgroups.com/forums/showthread.php?p=3631176&postcount=24

Warske

[CrashingDutchman]

Since Brett has everything ready, I would love to hear from him. The prices he mentioned sound great!

[badcockr]

Would love to go, but since I am from The Netherlands, it's a bit far...

CD

You could always go to www.farnell.com (sales across world)

Look for parts:
233596
327815
.... and similar

and the fibre as 5014864

HTH

Rod

[Warske]

...Could someone help me with basic electronics terminology? It seems I could choose from a "photodiode", "phototransistor", "photodarlington", and "photologic detectors" with either "totem pole" or "open collector" outputs.

...Which receiver part should i use, ideally I want an output of only either 0V or 5V with no swing in between, with a high signal on the LED side corresponding with a "on" state in the optical fibre and a high signal coming out of the receiver part. Based on your description, you want the photologic detector with totem pole output, but any of them could be made to work and I would be tempted to use the phototransistor for shorter distance (a few yards) since it is cheaper.

As to which each of them mean, Google should help clairify it, but basically its:

"photodiode" - probably will need a transistor to amplify it
"phototransistor" - has built in transistor
"photodarlington" - has 2 transistors for more amplification
"photologic detectors" - has transistor and circuit to give you high or
low output with clean transisiton.
"totem pole" - output will both source and sink current
"open collector" - output will only sink current Good luck

Warske

[Brett_Warwick]

I bought the if-e96 at my local electronics shop..Jaycar its also available here.

http://www.web-tronics.com/if-e96.html

http://www.esssales.com/ifo/photodetectors/if-e96.html

http://www.digikey.com/

Being all plastic it is very light about 10grams all up.

Here is a pic of the circuit i basically used.

The little rx/tx fiber units just make it neat and the clamp connector tightens onto the fiberoptic making it a very robust connection.

If youve never experianced interferance problems you may say whats the point. but if you have then this is fantastic.

Hope this helps

Brett

[Warske]

Here is a pic of the circuit i basically used. That looks familiar! Glad it turned out to be useful. :)

Warske

[CrashingDutchman]

Brett,

Thanks, this will help for sure!

Cheers,

CD

[CrashingDutchman]

Hi Brett,

I am about to contact esssales.com for ordering the items for this opto link. Could you please check this:
http://www.esssales.com/ifo/photodetectors/if-e96.html
and this:
http://www.esssales.com/ifo/photodetectors/if-d96.html

A combination of these 2 and some optical wire is enough? Is that what you are using?

Thanks,

CD

[Brett_Warwick]

Hi CrashingDutchman,

Yep and just follow the circuit above.. it works a treat. why are you building this anyway..do you have an interferrence problem..

By the way cut your optical fiber with a sharp knife..Hopefully youll get the plastic type fiberoptic and not the glass stuff. Then using the finest sandpaper 1200+ with a little water polish the ends flat using figure 8 movementon the paper keeping it as square as possible. its probley not nessesary but its what your ment to do for maximum light transfer

[lostrider]

So, We Can Use This Part For Extra Esc Or Servo, For Extra Control.
All Our Need Is Connecting Rx Side To An A Coder, And Using Fisheye Glass For Ir Leds (maybe 4-8 Led Needed), And Stick Or Pot Control On The Coder,
It Will Be Cool For Ground Operations:d
Who Can Be Design An A Coder For Rx Side Signals?

[badcockr]

By the way cut your optical fiber with a sharp knife..Hopefully youll get the plastic type fiberoptic and not the glass stuff. Then using the finest sandpaper 1200+ with a little water polish the ends flat using figure 8 movementon the paper keeping it as square as possible. its probley not nessesary but its what your ment to do for maximum light transfer

It is not necessary to 'polish' with greater than 1200 paper on plastic fibre - this induces scratches that cause the light to scatter and increases the loss from that obtained using a sharp blade.

HTH

Rod

[Zlatko]

Hi All,

Very good idea, thank you.

lostrider, if you get bored have a look here http://www.rcgroups.com/forums/showthread.php?t=24711 .
Its about DIY IR control for room fliers, only about 170 pages short ;)

Cheers
Zlatko

[lostrider]

thanks zlatko,
its my favorite thing,
but i canf find time for this thing,
thanks for source, im in there now

[CrashingDutchman]

Hi CrashingDutchman,

Yep and just follow the circuit above.. it works a treat. why are you building this anyway..do you have an interferrence problem..



I sometimes have interference problems. This is a nice way to find out if I can get rid of it completely.

Thanks!

CD

[CrashingDutchman]

Sorry to 'awake' this thread again....

While browsing a electronics catalogue, I found some optically coupled isolator ic's. Anyone with experience with those ic's?

Here is a link to a datasheet of one of the ic's I found (PDF):
http://www.produktinfo.conrad.com/datenblaetter/175000-199999/185604-da-01-en-mct_2_pc_613.pdf

CD

[vintage1]

Not true for the cable used here.

Communications optical fibre is 125 um silica fibre (monomode) which can only be cleaved using specialist tools that a modeller will not have.



Are you sure? For up to a kilometer transmission or so most fibre I have come across is multimode...


This fibre is 1 mm PMMA plastic optical fibre (POF) typically used in automotive systems or in optical links for audio systems. Handling is very easy and the fibre is cheap and easily available. No specialist tools are required apart from a sharp blade to cut (cleave) the fibre. Because of the large diameter this poses no safety problems.

HTH

Rod

Which is good news..

[vintage1]

I sometimes have interference problems. This is a nice way to find out if I can get rid of it completely.

Thanks!

CD
You can never get rid of it completely: Just get it small enough...

[CrashingDutchman]

Of course, I understand that!

Any idea on my question using optically coupled isolator ic's? Would this work?

CD

[jperch]

Optical isolator IC's have been used for interference reduction for some time. Most often, they work quite well. However, sometimes RF interference has been known to get across the IC's because of their short physical dimensions. The point of using this optical fiber was to increase the physical separation of the transmitter and receiver. It is basically another way to solve the same problem.

Joe

[CrashingDutchman]

I understand... I would have to try it to know if it helps.

Thanks Joe,

CD